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Estimating ocean tide loading displacements with GPS and GLONASS / Bogdan Matviichuk in Solid Earth, vol 11 n° 5 (September - October 2020)
[article]
Titre : Estimating ocean tide loading displacements with GPS and GLONASS Type de document : Article/Communication Auteurs : Bogdan Matviichuk, Auteur ; Matt A. King, Auteur ; Christopher S. Watson, Auteur Année de publication : 2020 Article en page(s) : pp 1849 - 1863 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] données GLONASS
[Termes IGN] données GPS
[Termes IGN] estimation de position
[Termes IGN] surcharge océaniqueRésumé : (auteur) Ground displacements due to ocean tide loading have previously been successfully observed using Global Positioning System (GPS) data, and such estimates for the principal lunar M2 constituent have been used to infer the rheology and structure of the asthenosphere. The GPS orbital repeat period is close to that of several other major tidal constituents (K1, K2, S2); thus, GPS estimates of ground displacement at these frequencies are subject to GPS systematic errors. We assess the addition of GLONASS (GLObal NAvigation Satellite System) to increase the accuracy and reliability of eight major ocean tide loading constituents: four semi-diurnal (M2, S2, N2, K2) and four diurnal constituents (K1, O1, P1, Q1). We revisit a previous GPS study, focusing on 21 sites in the UK and western Europe, expanding it with an assessment of GLONASS and GPS+GLONASS estimates. In the region, both GPS and GLONASS data have been abundant since 2010.0. We therefore focus on the period 2010.0–2014.0, a span considered long enough to reliably estimate the major constituents. Data were processed with a kinematic precise point positioning (PPP) strategy to produce site coordinate time series for each of three different modes: GPS, GLONASS and GPS+GLONASS. The GPS solution with ambiguities resolved was used as a baseline for performance assessment of the additional modes. GPS+GLONASS shows very close agreement with ambiguity resolved GPS for lunar constituents (M2, N2, O1, Q1) but with substantial differences for solar-related constituents (S2, K2, K1, P1), with solutions including GLONASS being generally closer to model estimates. While no single constellation mode performs best for all constituents and components, we propose to use a combination of constellation modes to recover tidal parameters: GPS+GLONASS for most constituents, except for K2 and K1 where GLONASS (north and up) and GPS with ambiguities resolved (east) perform best. Numéro de notice : A2020-837 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.5194/se-11-1849-2020 Date de publication en ligne : 14/10/2020 En ligne : https://doi.org/10.5194/se-11-1849-2020 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98169
in Solid Earth > vol 11 n° 5 (September - October 2020) . - pp 1849 - 1863[article]Integration of airborne gravimetry data filtering into residual least-squares collocation: example from the 1 cm geoid experiment / Martin Willberg in Journal of geodesy, vol 94 n° 8 (August 2020)
[article]
Titre : Integration of airborne gravimetry data filtering into residual least-squares collocation: example from the 1 cm geoid experiment Type de document : Article/Communication Auteurs : Martin Willberg, Auteur ; Philipp Zingerle, Auteur ; Roland Pail, Auteur Année de publication : 2020 Article en page(s) : n° 75 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] collocation par moindres carrés
[Termes IGN] Colorado (Etats-Unis)
[Termes IGN] filtre passe-bas
[Termes IGN] géoïde gravimétrique
[Termes IGN] géoïde local
[Termes IGN] gravimétrie aérienne
[Termes IGN] levé gravimétrique
[Termes IGN] modèle stochastique
[Termes IGN] pondération
[Termes IGN] processus gaussienRésumé : (auteur) Low-pass filters are commonly used for the processing of airborne gravity observations. In this paper, for the first time, we include the resulting correlations consistently in the functional and stochastic model of residual least-squares collocation. We demonstrate the necessity of removing high-frequency noise from airborne gravity observations, and derive corresponding parameters for a Gaussian low-pass filter. Thereby, we intend an optimal combination of terrestrial and airborne gravity observations in the mountainous area of Colorado. We validate the combination in the frame of our participation in ‘the 1 cm geoid experiment’. This regional geoid modeling inter-comparison exercise allows the calculation of a reference solution, which is defined as the mean value of 13 independent height anomaly results in this area. Our result performs among the best and with 7.5 mm shows the lowest standard deviation to the reference. From internal validation we furthermore conclude that the input from airborne and terrestrial gravity observations is consistent in large parts of the target area, but not necessarily in the highly mountainous areas. Therefore, the relative weighting between these two data sets turns out to be a main driver for the final result, and is an important factor in explaining the remaining differences between various height anomaly results in this experiment. Numéro de notice : A2020-536 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-020-01396-2 Date de publication en ligne : 03/08/2020 En ligne : https://doi.org/10.1007/s00190-020-01396-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95729
in Journal of geodesy > vol 94 n° 8 (August 2020) . - n° 75[article]Benefits of combining GPS and GLONASS for measuring ocean tide loading displacement / Majid Abbaszadeh in Journal of geodesy, vol 94 n° 7 (July 2020)
[article]
Titre : Benefits of combining GPS and GLONASS for measuring ocean tide loading displacement Type de document : Article/Communication Auteurs : Majid Abbaszadeh, Auteur ; Peter J. Clarke, Auteur Année de publication : 2020 Article en page(s) : n° 63 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] constellation GLONASS
[Termes IGN] données GLONASS
[Termes IGN] données GPS
[Termes IGN] données marégraphiques
[Termes IGN] marée océanique
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement ponctuel précis
[Termes IGN] surcharge océanique
[Termes IGN] trajet multipleRésumé : (auteur) GPS has been used to estimate ocean tide loading (OTL) height displacement amplitudes to accuracies of within 0.5 mm at the M2 frequency, but such estimation has been problematic at luni-solar K2 and K1 frequencies because they coincide with the GPS orbital period and revisit period, leading to repeating multipath and satellite orbit errors. We therefore investigate the potential of using the GLONASS constellation (with orbital period 11.26 h and true site revisit period of 8 sidereal days distinct from K2 and K1) for OTL displacement estimation, analysing 3–7 years of GPS and GLONASS data from 49 globally distributed stations. Using the PANDA software in kinematic precise point positioning mode with float ambiguities, we demonstrate that GLONASS can estimate OTL height displacement at the M2, N2, O1 and Q1 lunar frequencies with similar accuracy to GPS: 95th percentile agreements of 0.6–1.3 mm between estimated and FES2014b ocean tide model displacements. At the K2 and K1 luni-solar frequencies, 95th percentile agreements between GPS estimates and model values of 3.9–4.4 mm improved to 2.0–2.8 mm using GLONASS-only solutions. A combined GPS+GLONASS float solution improves accuracy of the lunar OTL constituents and P1 (but not significantly for K1 or K2) compared with a single-constellation solution and results in hourly-to-weekly spectral noise very similar to a GPS ambiguity-fixed solution, but without needing uncalibrated phase delay information. GLONASS estimates are more accurate at higher compared with lower latitudes because of improved satellite visibility, although this can be countered by using a lower elevation cut-off angle. Numéro de notice : A2020-535 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-020-01393-5 Date de publication en ligne : 08/07/2020 En ligne : https://doi.org/10.1007/s00190-020-01393-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95727
in Journal of geodesy > vol 94 n° 7 (July 2020) . - n° 63[article]Rethinking error estimations in geospatial data: the correct way to determine product accuracy / Qassim Abdullah in Photogrammetric Engineering & Remote Sensing, PERS, vol 86 n° 7 (July 2020)
[article]
Titre : Rethinking error estimations in geospatial data: the correct way to determine product accuracy Type de document : Article/Communication Auteurs : Qassim Abdullah, Auteur Année de publication : 2020 Article en page(s) : pp 397-403 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Topographie moderne
[Termes IGN] cartographie numérique
[Termes IGN] détection d'erreur
[Termes IGN] données localisées
[Termes IGN] ellipsoïde (géodésie)
[Termes IGN] estimation de précision
[Termes IGN] nivellement direct
[Termes IGN] point d'appui
[Termes IGN] réalité de terrain
[Termes IGN] système de référence géodésique
[Termes IGN] système de référence localRésumé : (Auteur) Numéro de notice : A2020-380 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.14358/PERS.86.7.397 Date de publication en ligne : 01/07/2020 En ligne : https://doi.org/10.14358/PERS.86.7.397 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95425
in Photogrammetric Engineering & Remote Sensing, PERS > vol 86 n° 7 (July 2020) . - pp 397-403[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 105-2020071 SL Revue Centre de documentation Revues en salle Disponible The impact of terrestrial gravity data density on geoid accuracy: case study Bilogora in Croatia / Olga Bjelotomić Oršulić in Survey review, vol 52 n° 373 (July 2020)
[article]
Titre : The impact of terrestrial gravity data density on geoid accuracy: case study Bilogora in Croatia Type de document : Article/Communication Auteurs : Olga Bjelotomić Oršulić, Auteur ; Danko Markovinović, Auteur ; Matej Varga, Auteur ; Tomislav Basic, Auteur Année de publication : 2020 Article en page(s) : pp 299 - 308 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Croatie
[Termes IGN] données CHAMP
[Termes IGN] géoïde
[Termes IGN] gravimétrie terrestre
[Termes IGN] levé gravimétrique
[Termes IGN] quasi-géoïde
[Termes IGN] station d'observationRésumé : (auteur) One of the main challenges in physical geodesy today is achieving the 1-centimetre gravimetric quasi-geoid model, since a model of such accuracy could be used in the definition and realisation of the height reference frame. One of the main obstacles in this challenge is the lack of terrestrial gravity data or its uneven distribution. Therefore, the main question arises: what density of gravity points is necessary in order to obtain a gravimetric quasi-geoid model with an accuracy of 1 centimetre or even better? In this simulated study, the results show a trend of decreasing RMS related to the sparser dataset used in computation, leading to the conclusion that the determination of the sub-centimetre quasi-geoid model is no longer a theory, but can be achieved with the exact density of terrestrial gravity data: gravity observation stations have to be distributed no farther than 500 m from one another. When dealing with a very rough topography, the distance should be even shorter. Numéro de notice : A2020-456 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2018.1562747 Date de publication en ligne : 13/01/2020 En ligne : https://doi.org/10.1080/00396265.2018.1562747 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95555
in Survey review > vol 52 n° 373 (July 2020) . - pp 299 - 308[article]Past and present ITRF solutions from geophysical perspectives / Laurent Métivier in Advances in space research, vol 65 n° 12 (15 June 2020)PermalinkAltimétrie de précision autour du détroit d'Ormuz : détermination d'un géoïde gravimétrique, d'altitudes orthométriques précises et de la variation du niveau moyen de la mer / Jean-Louis Carme in XYZ, n° 163 (juin 2020)PermalinkThe direct geodesic problem and an approximate analytical solution in Cartesian coordinates on a triaxial ellipsoid / Georgios Panou in Journal of applied geodesy, vol 14 n° 2 (April 2020)Permalink40 ans de géodésie à l'IGN (Institut Géographique National rebaptisé en 2012 Institut national de l'information géographique et forestière) : 2ème partie, la géodésie physique / Françoise Duquenne in XYZ, n° 162 (mars 2020)PermalinkRecent sea level change in the black sea from satellite altimetry and tide gauge observations / Nevin Betül Avsar in ISPRS International journal of geo-information, vol 9 n° 3 (March 2020)PermalinkValidation of marine geoid models by utilizing hydrodynamic model and shipborne GNSS profiles / Sander Varbla in Marine geodesy, Vol 43 n° 2 (March 2020)PermalinkITRF2014, Earth figure changes, and geocenter velocity: Implications for GIA and recent ice melting / Laurent Métivier in Journal of geophysical research : Solid Earth, vol 125 n° 2 (February 2020)PermalinkAnalyse des surcharges hydrologiques observées par géodésie spatiale avec l’outil Multi Singular Spectrum Analysis / Louis Bonhomme (2020)PermalinkAssessment of ArcGIS based extraction of geoidal undulation compared to National Geospatial Intelligence Agency (NGA) model – A case study / Sher Muhammad in Journal of applied geodesy, vol 14 n° 1 (January 2020)PermalinkCaractérisation de la contribution des charges hydrologiques, atmosphériques et océaniques aux séries temporelles de position GNSS : analyse comparée des modèles de charge et de mouvement du géocentre / Elie-Alban Lescout (2020)Permalink